Mortise gauge



ll A32,

EDWARD A. MOLLER, OF BALTIMORE, MARYLAND.

MORTISE GAUGE.

Application filed August 14, 1920.

i '0 will whom it may concern:

Be it known that I, EDWARD A. MoLLER, a citizen of the United States of America, residing in the city of Baltimore, State of Maryland, have invented certain new and useful Improvements in Mortise Gauges, of which the following is a specification.

lhe operation of installing mortise locks involves a considerable amount of care and expenditure of time by a skilled carpenter in cutting and in locating the mortise, in or-- der that the lock may fit the mortise andbe firmly and correctly seated and accurately placed. In cutting the mortise, thebulk of the wood is ordinarily removed by means of an auger, a line of circular holes being bored and the mortise completed and squared with the chisel. The difficulties encountered in cutting the mortise have to do with the accurate placing of the auger holes and the lack of any convenient means for guiding the tools, also a considerable amount of time and skill are expended in locating and mark ing the mortise, preliminary to cutting.

The present invention relates to a gauge, clamp and guide by which themortise is located and the tools are guided in cutting the mortise; so that having set the tool for the dimensions and location of the mortise, it is merely ner-essary to clamp the gauge to the door at the desired elevation of the lock, to provide a fixed guide for the auger and chisel by means of which the most unskilled operator is enabled to cut and accurately l0- cate a mortise and do it with exactness as to dimensions, with the least possible expenditure of time, and much more quickly than the same operation is now performed by skilled workmen.

If a number of locks of similar size are to be similarly located, as in the construction of a building, this device is of great advan tage as it requires but one setting under these circumstances for the entire operation of cutting the mortises for all the locks.

A gauge embodying my invention in the preferred form is illustrated in the accompanying drawing, in which- Figure 1 is a side elevation of the gauge as applied to a door, showing the edge of the door.

Figure 2 is an levation at right angles to Figure 1.

Figure 3 is a plan View taken either from the top or bottom.

Serial No. 403,622.

Figure 41 is a section on the line 4-4 of Figure 2.

Referring to the drawings by numerals: the device consists of a clamp member 1, which is U shaped, as seen in plan Figure 3, and a plurality of guiding gauge menu here, 2

In the preferred. form of the invention, illustrated, the clamp is graduated as to the cross arm of the U at 3, to indicate the position of the gauge members relatively to the surfaces of the door as determined by the fixed jaw of the clamp. The clamp, as aforesaid, is of the U shape or jaw type, comprising a fixed jaw, 5, and a screw or other suitable type of clamping jaw, 6, threaded through the otherv arm, 7, of the U opposite and cooperating with the fixed aw, 5. As shown, the base or crossarm, 3, of the U clamp presents to the inside of the U a flat surface, 8, at right angles to the inner hearing face or abutment, 9, of. the fixed jaw, 5, and the scale, 3, preferably reads from, i e: has its zero mark or other convenient known point in the plane of the flat surface, 9, of

the fixed jaw, 5.

Considering the device as shown in figures 1 and 2, the clamping jaw member, 1, or more particularly the cross arm, 3, is in the form of a rectangular frame, which in effect consists of two similar transverse members, 10, as already described, spaced apart, and connected by longitudinal webs, 16 and 11, the web, 16, being in effect, included in the fixed jaw member, 5, already described, and the web, 11, in. the jaw, 7. r

The members, 10, are sloted-at 141 at right angles to the flat surface, 9, which may be referred to as the principal abutment, the slots being opposite and preferably of similar extent, the gauge members, 2, having opposed fiat gauge surfaces, 12, being mounted be tween the members, 10, and held in various positions of adjustment by means of set screws, 13, two of which are seated in each of the slots, 14, in the members, 10, one being threaded into each end of each corresponding gauge, 12, and the frame members, 10, and the gauge members, 2, being provided with co-operating and sliding guiding surfaces, 141, so that alignment of the gauge surfaces parallel to the abutment surface, 9, is maintained throughout the var ious positions of adjustment.

In operation, the spacing of the lock from one surface of the door havng been determined, one of the gauges, 12, is set opposite a point on a scale corresponding to the space thus determined and the width of the lock and hence of the mortise being known, the other gauge member, 12, is set at a point on the scale spaced from the point on the scale at which the opposite gauge is set by an interval slightly greater than the width of the lock, the set screws, 13, being securely tightened to prevent displacement of the parts, and the height at which the lock is to be placed on the door being known, the gauge is affixed to the door by passing the clamp over the edge of the door until the edge surface, 15, of the door, rests against the inside surface, 8, of the gauge, the abutment, 9, resting against the front surface, 16, of the door from which the measurements are to be taken. Clamping jaw, 6, is then tightened, rigidly securing the device to the door. Then a drill or auger, of a diameter as near to the spacing of the gauges as can be obtained, is employed to remove the wood between the gauges to a depth approximating and slightly exceeding the desired depth of the mortise as indicated at 18, the gauge surfaces serving most efliciently as a guide for this purpose and following this, the projecting parts are cut away with a chisel, the same being guided by the gauges, as aforesaid, forming a rectangular opening or mortise, as desired.

lVhile I have described the gauge as particularly adapted for use in installing looks, it may be used in cutting mortises for any purpose.

I have thus described specifically and in detail a mortise gauge embodying my in vention in its preferred form, in order that the nature and operation of same may be clearly understood. However, the specific terms herein are used descriptively rather than in a limiting sense, the scope of the invention being defined in-the claims.

' What I claim and desire to secure by Letters Patent is:

1. A mortise gauge consisting of a clamp having positioning surfaces at right angles to each other and a clamping jaw opposite one of said positioning surfaces, two gauge members having guide surfaces parallel to said latter surface one said member being mounted for adjustment at right angles to said surface.

2. A mortise gauge consistlng of a clamp 1 ,aeaaes one of said positioning surfaces, two, gauge members having guide surfaces parallel to sald lattter surface one said member being mounted for adjustment at right angles to said surface, scale graduations on said clamp arranged to measure distances in a direction at right angles to said guage surfaces and adapted to determine the position of each said gauge surface in relation to the said latter positioning surface of the clamp.

3. A mortise gauge consisting of a clamp having a fixed jaw with a fiat positioning surface and a movable jaw adjustable toward and from said positioning surface to clamp thematerial to be mortised between the said movable jaw and said positioning surface, the clamp comprising a frame composed of two cross arms, spaced apart, and longitudinal members holding them in spaced relation, gauge members between said cross arms having gauge surfaces parallel to the positioning surface of the clamp, the same being adjustable in a direction at right angles to said guage surfaces and means for securing the gauge members in various positions of adjustment, relatively to the clamp.

4. A mortise gauge consisting of a clamp having a fixed jaw with a flat positioning surface and a movable jaw adjustable toward. and from said positioning surface to clamp the material to be mortised between said movable aw and said positioning surface, the clamp comprising a frame composed of two cross arms, spaced apart, and held in rigid relation, and longitudinal members holding them in spaced relation,

gauge members between said cross arms" EDWARD A. MULLER.

Witnesses:

PORTER H. FLAUTT, ANNA BERNSTEIN.

gauge surfacesto said position I 

